Fluidborne sound projector

The present invention relates generally to the translation of acoustical energy into a body of liquid such as water from a high power acoustical source.

BACKGROUND OF THE INVENTION

Acoustical energy projector devices, such as a fluidborne noise source delivering underwater sound are generally known in the art. Such projector devices when adapted for use in a piping system operating under high pressures of up to 1000 psi for example, have been found to be unsuitable because of their fragility, subjecting it to damage during operation and its inability to deliver acoustical energy at a relatively high power level. It is therefore an important object of the present invention to provide an acoustical projector of fluidborne sound or noise within a wide acoustical spectrum, with a monitored input under control and to prevent damage due to changing system pressures entrapped in the delivery device.

SUMMARY OF THE INVENTION

In accordance with the present invention, an acoustical projector device is provided for a fluidborne noise generating system, within which input acoustical energy at controllable power level is translated to a body of liquid through a piston undergoing displacement to a static position within a pressure sealed chamber assembly through which gas and liquid are applied to the piston under automatically balanced pressures, with further regulated positioning of the piston being effected by controlled pressurization and venting of the gas within the piston chamber. Displacement of the piston is also mechanically limited to prevent damage by changing operational pressures exerted thereon to thereby accommodate a wide diversity of characteristics of the acoustical energy to be translated, such as sound frequencies, tones, bands and wave forms.

BRIEF DESCRIPTION OF DRAWING FIGURES

A more complete appreciation of the invention and many of its attendant advantages will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawing wherein:

FIG. 1

is a side elevation view of an acoustical projector device in accordance with one embodiment, in association with other components of a fluidborne noise generating system;

FIG. 2

is a transverse section view of the projector device, taken substantially through a plane indicated by section line

2

—

2

in

FIG. 1

;

FIG. 3

is a partial section view taken substantially through a plane indicated by section line

3

—

3

in

FIG. 2

;

FIG. 4

is a side section view of the projector device taken substantially through a plane indicated by section line

4

—

4

in

FIG. 2

; and

FIG. 4A

is an enlarged portion of the section view of

FIG. 4

, illustrating mechanical limiting of piston displacement in the projector device.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

Referring now to the drawing in detail,

FIG. 1

illustrates a fluidborne noise generating system generally referred to by reference numeral

10

, having an acoustic projector device

12

constructed in accordance with the present invention for supply of fluidborne sound through at tubular output conduit

14

to a liquid retention facility such as a water piping system, a tank or a sea chest. An external source of sound for the projector device

12

is derived from an electromechanical or piezoelectric type shaker

16

, generally known in the art, attached to a tubular input end portion

18

of the projector device

12

. The tubular input portion

18

axially projects through an annular section

20

of the projector device

12

into an abutting annular projector section

22

in slidably sealed relation to the section

20

. The projector sections

20

and

22

are held in assembled attachment to the tubular output conduit

14

through an annular flange portion

24

thereof by a plurality of threaded fastener bolts

26

. As shown in

FIGS. 1

,

2

and

3

, each of such fastener bolts

26

has at one axial end a head portion

28

abutting the projector section

20

and is threaded at its opposite axial end for reception of a nut

30

in abutment with the conduit flange portion

24

closely spaced from the projector section

22

by a gasket seal

32

.

With continued reference to

FIG. 1

, in accordance with one embodiment of the sound generating system

10

with which the projector device

12

is associated, an amplified electrical power source

34

delivers a driving signal

36

through wiring

38

to the shaker

16

under control of an input signal in wiring

40

generated by an acoustic spectrum analyzer system

42

in accordance with different variable sensor data from analyzer modules

44

,

46

and

48

. The analyzer module

44

is connected by a sensor output signal line

49

to the tubular input portion

18

of the projector device

12

, while the analyzer modules

46

and

48

are respectively connected by hydrophonic and accelerometer pressure signal lines

50

and

52

to monitoring taps

54

and

56

on the tubular output conduit

14

of the projector device

12

. Gas venting and liquid pressure controls are also provided for the projector device

12

, as hereinafter explained, through pressure monitoring lines

58

and

60

respectively connected to the projector sections

20

and

22

by taps

59

and

61

. Such pressure monitoring lines

58

and

60

are respectively connected to opposite ends of a pressure-tight tank

62

for respective communication with pressurized bodies of gas

64

and liquid

66

therein, as shown in FIG.

1

. Pressure is monitored through a tap

72

in the projector section

22

under control of valve

74

by a gauge

70

, while pressurized gas, such as air, is supplied to the projector section

20

through a tap

68

under gas venting control of a manually operated valve

75

. Venting of gas within the projector device

12

occurs through a radial passage

76

in projector section

22

as shown in

FIG. 4

, hereinafter referred to in connection with the internal details of the projector device

12

.

With continued reference to

FIG. 4

, the sound output of the shaker

16

is transmitted to the tubular input portion

18

of the projector device

12

at its external end through a connector

78

. Such tubular input portion

18

is connected at its internal end within the projector section

22

to a piston

80

at a larger diameter end

82

thereof. Axial displacement of the piston

80

is thereby induced within a larger diameter chamber

84

internally formed within the section

22

and terminating at one axial end of a smaller diameter chamber portion

86

within the projector section

20

, extending axially toward the gasket seal

32

through which acoustical energy is translated within a passage in the tubular conduit

14

along its axis in common with the axis

88

of the projector device

12

.

The projector section

22

as shown in

FIGS. 4 and 4A

has a portion

90

projecting into the section

20

and in interfitting relation thereto through an annular seal

92

. Another annual seal

94

is carried in the larger diameter portion

106

of the piston

80

to seal opposite end portions of the larger diameter chamber

84

from each other in the section

22

. A third annular seal

96

on the piston

80

in close adjacency to its smaller diameter end

98

is provided to seal chamber

86

from the axial end of the larger diameter chamber

84

into which gas venting passage

76

extends. The other axial end of chamber

84

is in communication through passages with the gas tap

59

to the tank

62

and the gas pressure tap

68

. Chamber

86

is also in communication with tank

62

through passage to the liquid tap

61

in section

22

as shown in

FIG. 1

, while pressurized liquid is received in chamber

86

through valve

74

and tap

72

.

It is apparent from the foregoing description that the external sound producing operation of the shaker

16

, isolated from water exposure, translates acoustical energy into vibratory movement of the piston

80

to a static position between displacement limits as shown in

FIGS. 4 and 4A

for projecting sound into liquid through conduit

14

at different sound frequencies under control exercised by balancing between pressures of the liquid and gas in chambers

84

and

86

through taps

59

and

61

. Such balancing is automatically performed by monitoring piston displacement velocity through an underwater type acceleration sensor

100

within the projector end portion

18

connected by signal line

49

as shown in

FIG. 4

to the data module

44

shown in

FIG. 1

for control over operation of the shaker

16

by the amplified power source

34

through the spectrum analyzer system

42

. Changing system pressure during such automatically controlled operation is affected by limiting displacement of the piston

80

within chamber

84

. As shown in

FIG. 4A

, the diametrically larger chamber

84

extends axially between an annular stop surface

102

in the projector section

20

and a radially smaller annular stop surface

104

on the projector section

22

. A diametrically larger portion

106

of the piston

80

is engageable with such stop surfaces

102

and

104

to limit its displacement. Also, the position of piston

80

between stops

102

and

104

is regulated by pressurized gas supplied to chamber

84

through tap

68

, while the gas therein is vented at one axial end through passage

76

. Pressurized air at the other axial end portion of chamber

84

is monitored by gauge

70

through tap

68

. Pressurized gas is accordingly added to chamber

84

or vented therefrom while damage from changing system pressures from chamber portion

86

is prevented and different types of sound and a diversity of wave forms is accommodated under control of the drive signals generated by the spectrum analyzer system

42

.

Obviously, other modifications and variation of the present invention may be possible in light of the foregoing teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.